When you consider his track record, his actions toward Reiner seem odd. He murdered a member of Kenny's team in the Reiss cave while staring at his dying face. He was going to take down Falco and Pieck in this arc. So why would he restrain Hange when they were executing Reiner? When it comes to Pieck's injuries, I believe they took longer to recover since the Cart isn't designed for quick regeneration or Reiner's armored cockroach power. As a result, Pieck is most likely out of commission for the time being.
History
The War Hammer Titan, like the other Nine Titans, was born following the death of Ymir Fritz. The War Hammer Titan was retained in the grip of one or more of the warring Eldian households obedient to the Founding Titan for the 1,700 years after her death. The War Hammer Titan had fallen into the property of the Tybur family after these seventeen centuries, when King Karl Fritz abandoned the battles of Eldia and retreated to Paradis Island. The rebellious peoples of Marley did take part in the Great Titan Battle at some time, and the Tybur family were the first Eldians to come to their help in the early days of the war. [16] [17] [18]

